Seamless tubes from mandrels



no Model.) 2 SheetsShee-t i.

R. F. HALL, F. WARWICK & T. SMITH. MEANS FOR REMOVING QFIAMLESS TUBESFROM MANDRELS.

310.577.2965. Patented. Feb. 16, 1897.

N5 Model.) 2'Shets-Sfleet 2.

R. F. HALL, 1?.WARWIGK &-T. SMITH. MEANS FOR REMOVING SBAMLESS TUBESFROM MANDRELS.

No. 577,296. Patented Feb. 16, 1897.

- 1 a Z a & 51 v 0' b w| NESS-ES I INVENTORS fie rZJfIaZZ. flf f w .Z wmz i /T M mingham,

" UNITED STATES PAT NT OFFICE.

ROBERT HALL, FREDERICK WARWICK, AND THOMAS SMITII, or

- BIRMINGHAM, ENGLAND.

MEANS Fen REMOVING SEAMLESS'TUBES FROM MANDRELS.

SPECIFICATION forming part of Letters Patent No. 577,2 96, datedFebruary 16, 1897.

\ Application filed June 1, 1896. Serial No. 593,876. (No model.)

T aZZ whom it may concern:

Be it known that we, ROBERT FREDERICK HALL, of SherlockStreet, in thecity of Bir- FREDERICK WARWICK, of the Dingles/ Shirley, nearBirmingham, and THOMAS SMITH, of Wharf Street, Aston, near Birmingham,England, have invented certain new and useful Improved Means forRemoving Seamless Steel Tubes from Mandrels, of which the following is aspbcification.

This invention relates to an improved and simplified machine forremoving seamless complished by what is known steel or other tubes fromtheir mandrels.

In manufacturing weldless steel tubes produced upon solid mandrels it isdifficult to withdraw the tube from off the mandrel or to remove, themandrel from the tube, and this is done often at a great risk ofinjuring the constitution of the metal from whichthe said tube is made.The removal is usually acas a reelingmachinefl which rotates the tubeand'mandrel together and by applied pressure slightly spreads orincreases the internal diameter of the tube formed and thereby loosensthe same on the mandrel, when the said tube can be easily withdrawn.

The removal of thin gage-tubes (such as are usually used in cycle-work)is fraught with difficulties on account of the liability of the same tobe externally injured and scratched, and oftentimes they burst.

According to our improvements the walls of a drawn tube are loosen edfrom its mandrel by a straight rolling process, which consists inpassing the tube while on the mandrel between two counterpart rolls, oneof' which is mounted directly above the other, and each roll having aV-shaped groove in its periphery, so that the walls formed by the saidgrooves will bear against the tube at four distinct and separated pointsto secure four distinct clearance-spaces, which admit of the flowing ofthe metal displaced, it being understood that this is accomplished witha single pair of rolls. In order to enable others skilled in the art tomake, use, and practice our invention, we will now proceed to describethe same in detail, reference being had for this purpose to theaccompanying drawings, in which Figure 1 represents a front elevation ofa Fig. 2 is a located The letters a and 1) indicate a pair of rollslocated one above the other and each having a V-shaped groove in itsperiphery forming the inclined walls a a and b b. The upper roll a isprovided with axles or journals a a which are mounted to run freelywithin the bearings e formed in the ends 6 of an adjustable stirrup cThis stirrup is arranged to slide vertically in guides'formed in thebolster or frame d, and may be adjusted to various heights with respectto the lower roll by means 7 of the hand-screw f. The lower roll videdwith similar axles or journals b 12 which are loosely mounted in t ebearings 0, formed in or carried by the bolster or frame d. Thereference-letter 9 indicates a bar or 8 mandrel, and h is the tube,formed upon said mandrel, and which is to be loosened and removed asfollows: The tube and mandrel are forced or drawn through thesubstantially angular space'formed between the two rolls 8 by theinclined walls a a and b b, said tube coming in contact with the saidinclined walls at four separate and distinct points, as shown, andbetween each pair of contact-points is a clearance-space i (four in all)to admit of the expansion or flow of the displaced metal. The bore ofthe tube is thereby slightly enlarged, so as to admit of the same beingeasily, stripped from the mandrel.

It is to be noted that the tube is acted upon 9 at four separate anddistinct points by the single pair of rolls, this being-accomplished bythe peculiar shape of the groove in the periphery of said rolls.

We are aware that it is broadly old to pro- I vide an apparatus forremoving tubes from their mandrels wherein the tubes are acted b isproupon 011 four different sides by two pairs of rolls, one pairbeingarranged at right angles to the other pair, and each roll having aconcaved groove in its periphery. By our invention we dispense entirelywith one pair of such rolls and accomplish the same result with a singlepair of peculiar construction.

What we claim is- A machine for releasing a tube from a mandrel,consisting of two counterpart rolls journa-led one above the other andeach having a V-shaped groove in its periphenv, the walls of which bearagainst the tube at [our dis-

